In simple English
This tool helps you build apps that handle money, like digital wallets or lending systems. It records every payment so nothing gets lost or out of balance. Writing this logic by hand takes months and causes bugs. Using this tool keeps your financial data accurate as your user base grows. It is free to run yourself, but you must host and maintain it on your own server.
What it is
Blnk is an open-source ledger written in Go (a compiled programming language made by Google for fast, reliable servers) that uses double-entry accounting principles. It provides an API (a set of rules that lets different software programs talk to each other) to record transactions, manage user balances, and match external bank statements.
What it is good for
Solo builders and small teams creating payment apps, wallets, rewards programs, or custom billing systems who need a reliable way to track balances without building financial software from scratch.
- Follows double-entry accounting standards out of the box so books always balance.
- Includes tools to match internal records against external bank statements.
- Handles complex workflows like scheduled payments, overdrafts, and bulk transactions.
- Requires a PostgreSQL (an open-source relational database program) instance to store records and run properly.
- Self-hosting means you are responsible for database backups, security patches, and server uptime.
- Go knowledge is needed if you want to modify the core source code rather than just use the API.
custom database tables and manual balance tracking logic
PostgreSQL
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git clone https://github.com/blnkfinance/blnk.git cd blnk docker compose up